Revolving hook for sewing-machines



(No Model.)

E. KOHLBB, & M LACHMAN.

REVOLVING vHOOK POR lSEWING MACHINBSf` Patented Deo. 4, 1888.

UNITED STATES PATENT OEEICE.-

EDIVARI) KOHLER, OF VEST OAKLAND, AND MORRIS LAOI-IMAN, OF SAN FRANCISCO, CALIFORNIA.

REVOLVING HOOK FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 393,766, dated December 4, 1888.

Application tiled September '7, 1887. Serial No. 248,993. (No model.) Patented in England April 29, 1887, No. 6,295.

To all whom it may concern:

Be it known that we, EDWARD KOHLER, of 861 Chester street, Test Oakland, California, United States of America, and MORRIS LACH- MAN, of 1810 Laguna street, San Francisco, California, United States of America, have invented certain new and useful Improvements in Sewing-Machines, of which the following is a specification, the said improvements being embraced in the Letters Patent ot' Great Brit ain No. 6,295, of April 29, 1887.

This invention relates to that class of sewing-machines in which a single thread for the production of a chain-stitch is used, the principal obj ects of the invention being to increase the speed of working and to improve the strength and quality of the sewing.

Our invention is applicable to various constructions of single-thread sewing-machines in which a horizontal shaft is provided below the table. To this shaft we fit a driver for rotating a loose looper of peculiar construction. This looper works in a fixed circular race, in front of which the vertical needle vibrates, to present its open loop to the nose of the looper.

' IVe have not considered it necessary to show our invention as adapted to a sewing-inachine, as the only change necessary for its adaptation is the fitting of the ordinary loopershaft with a driver for rotating the looper. The rotation of this looper will be continuous, and no change will be required in the timing of the reciprocating needle or in the timing of the feed.

Our improved looper is nearly annular in form, its perimeter extending over rather more than three-quarters of the circle. The nose of the looper is pointed and is of its greatest thickness vertically-that is, in the direction of the length of the needle-near its nose. From the nose the looper graduallyv decreases in vertical thickness and increases in lateral thickness to its heel, so as to open ont. the loop of the needle, and at its heel the looper is forked for the purpose ot' providing a space for the needle to pass into within. the plane of rotation ot the looper, in order to take the last-formed loop from the looper. The looper is secured in its circular race by a retainingring, which lts an annular rabbet in the face of the race, and the race we preferably form in one with the trout bearing ot' the shaft upon which the looper-driver is mounted.

In the accompanying drawings, Figure 1 shows the rotary looper in side, plan, and edge views, constructed on a scale to take loops of twine such as is used in sewing sacks. Fig. 2 shows the looper, its race, and driver in elevation and in sectional plan, the ring which retainsthe looper in its race being removed in the elevation to show the looper more clearly. Fig. 8 is a sectional elevation of the looper and its race, taken in the plane of the axis of the driving-shaft. Fig. f1 shows the driver detached in side and edge views. Figs. 5, 5, 6, 6, 7, 7a, 8, and 9 show the needle, the looper, and its driver in the successive positions which they take up during the formation of a stitch, the looper being represented in side view in Figs. 5, 7, S, and 9, and in plan at Figs. 5, 6, and 72 Referring' now to Figs. 2 and 3, A is the loose looper set in its race B, which is made fast to the framing C of the machine.

I) represents a horizontal shaft, on t-he end of which the driver E is mounted. The driver and the looper are so shaped with respect to each other as to provide for a loose interlocking of the parts, a slight play being allowed to provide for the free passage of the thread between them.

F is the vertical eye-pointed needle.

G indicates the table for supporting the work, which may be fed forward in the direction of the arrow, Fig. '7, either by a top or under feed device.

The form of the looper A is peculiar, and will be best understood by reference to Fig. 1. The nose a of` this looper is bent outward to meet the needle on its descent and pass through the loop which the needle has just brought down through the work and presented to the looper. The tail end of the looper is forked, the outer prong, a', being somewhat shorter and narrower than the inner prong, c2, :for the purpose to be presently explained. The thickness of the looper is, as will be seen, greatest vertically near the point or nose, and is decreased in vertical thickness from the point to the heel, while its lateral thickness is increased at the forked IOO port, und it thereh) serves to sprend the loop :is the looper in its rotntion passes through it. An opened loop is thus presented tio the point ol' the needle nt eneh succeeding deg seent of the sinne for the purpose of talking' up the loop ns the looperlenves it to enter the next sueeeetlineloop iornied h v the needle.

'lhe tnt-e otY the looper is rnhheted to perinit of its lying close ne'ninst the retaining'- ring l. vvheh is shown in pint-e in Fig: il, :ind detnehed und in side vie\v nt Fig'. 25". driver ll (shown detzu-hed at, Fig. l) is so shrtped ns to torni with the rnee n hed for the looper. Its extremity e strikes the tnil to ol" the looper nud ennses it to revolve in its rnee, hut lenves the looper l'ree to nvield to tht` drug' ol` the loop, and therehv lenve room for the loop to escape t'roin the tnil otf the looper. We hnve snid thnt the prongs o o? nre ot ditl'eront lengths. 'lhis provides t'or the loop lenving;` the looper g'raulnnllv, the needle in its dt sig-ent taking up the shit-lv' ns the thread esvnpes from the prong' o', :nid therehjvv onitneneing the operation ol` tightening; the st iteh before the loop tinnlly esenpeslroin the tail ol the looper. 'lhe nu-e l is re 1-essed,ns nt b, to provide tree plnv lor the do :endingl needle and for the escape ot' the loop from the looper. 'lo prevent the loop being enughti hy the angle formed by the. recess, the ang-le .1 looper.

t'roin the proneI o ot the loopor, the needle havingI deseended to n position i'or taking up the slnek.

Fig. i) shows the position ot' the parts when the looperhns passed through the loop und the pull oli' the descending' needle hns drown the loop from the longer prong, ft2, ol' thiI 'lhe return movement ol` the needle next opens out n loop l'or the looper to tnlv'e up, which will he ell'eeted h v the continued The notion ol' the driver bringing' the nose ol' the looper into the position shown :1t Fig. inviten `the operntions :there deserilied will he repented. "lhe eonipletion ol.' the stitch, it will he understood, is ell'eoted h v the rise ol' the needle tothe position ot' Fig. t3, while the lustlorlned loop is retained upon the looper. lt will he seen thnt the tnil end, o", ot the looper :ind the shoulder e ol' the drivernre severally rounded ol't'. This I'neilitntes the passage ol.' the esenpine loop troni lwtneeu these two eentnet-surl'nees.

llnving now pnrtit'ulurlv deserihed und :lseertuined the natur(I ol.' our snid inventitm and in what ninnner the snlno is to he pert'ornied, we doelnre tlntt whnt we oloiin isli 'lheronihinntion, with the rnee I3, ol' tho loose looper A find the rotniv driver t'ol opernt ing the loopen, substnntinll)v ns described, snnl loopt-r consistinl ot nn open ring having is extended outward, :is n tinger, :ity li, which I loop formed h v the needle, :ind its rear end l M or heel lorked to pernllt the pnssnge ot the will guide the escaping loop out of the rnee when being' drawn up to tension.

\Ve will now explain the notion of the nieehnnisin, relerenee heine; had to Figs. L. E, o, 7, s, and t).

its l'orwnrd end or nose pointed to enter the i needle throne-h the loop held by the, looper,

the vertieul thielcnoss oti' snid looper decreas- Fig. shows the needle rnised from its lowthe leed has tnlren plnee, the looper holding?r the opened-out loop in un inclined position7 ready for the desc-ending needle to enter it und carry through the next succeeding loop for presentation to the nose of the looper.

lnterid thickness inerensingnt the lorhed heel to Open out the loop, suhstnntinll)Y ns deserihed.

2. ',llle eoinhinntion, with the rneel, of the loose looper A, eonsisting oli' un open ringl having' its nose pointed to enter the loop rl'ornied b v the needle :ind its heel broadened und forked to permit.` the pnssnee ot' the needle through the loop held hy the looper, one prong; ol' snid vfork being shorter thnn the other, suhstnntinllv :is deserihed.

W it nesses:

A. (I. lnsnor,

Fig. S shows the loop in the net of esenping (lon.

Onmfxn l). Onvis,

Si. (ivory/Us (Ill/), Loot/on.

IOO 

